Nickel 200 and 201 have excellent corrosion resistance to caustic soda and other alkalis. They perform best in a reducing environment, but can also be used under oxidation conditions where a passivated oxide film is formed. They are used in aerospace, chemical and petrochemical processing, food processing, and Marine and water treatment applications. Both Nickel 200 and 201 are highly malleable over a wide temperature range and can be easily welded and machined with standard shop manufacturing practices.
Nickel 200 (UNS N02200) and 201 (UNS N02201) are two-factor certified forged nickel materials.
They differ only in the maximum amount of carbon present - 0.15 percent for Nickel 200 and 0.02 percent for Nickel 201.
Nickel 200 is generally limited to use at temperatures below 600ºF (315ºC) because at higher temperatures it may undergo graphitization, which can seriously impair performance.
At higher temperatures, nickel 201 plates should be used. Both grades are approved by the ASME Boiler and Pressure Vessel Code, Part VIII, Part 1. Nickel 200 plates are approved for use at temperatures up to 600ºF (315ºC), while Nickel 201 plates are approved for use up to 1250ºF (677ºC).
Both grades have excellent corrosion resistance to caustic soda and other alkalis. The alloy performs best in a reducing environment, but can also be used under oxidation conditions that produce a passivated oxide film. They are resistant to corrosion by distilled water, natural water, and moving seawater, but are subject to erosion by stagnant seawater.
Nickel 200 and 201 are ferromagnetic and exhibit high ductility mechanical properties over a wide temperature range.
Both grades can be easily welded and machined with standard shop manufacturing practices.